1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * KUnit test of ext4 inode that verify the seconds part of [a/c/m]
4 * timestamps in ext4 inode structs are decoded correctly.
5 */
6
7 #include <kunit/test.h>
8 #include <linux/kernel.h>
9 #include <linux/time64.h>
10
11 #include "ext4.h"
12
13 /*
14 * For constructing the nonnegative timestamp lower bound value.
15 * binary: 00000000 00000000 00000000 00000000
16 */
17 #define LOWER_MSB_0 0L
18 /*
19 * For constructing the nonnegative timestamp upper bound value.
20 * binary: 01111111 11111111 11111111 11111111
21 *
22 */
23 #define UPPER_MSB_0 0x7fffffffL
24 /*
25 * For constructing the negative timestamp lower bound value.
26 * binary: 10000000 00000000 00000000 00000000
27 */
28 #define LOWER_MSB_1 (-(UPPER_MSB_0) - 1L) /* avoid overflow */
29 /*
30 * For constructing the negative timestamp upper bound value.
31 * binary: 11111111 11111111 11111111 11111111
32 */
33 #define UPPER_MSB_1 (-1L)
34 /*
35 * Upper bound for nanoseconds value supported by the encoding.
36 * binary: 00111111 11111111 11111111 11111111
37 */
38 #define MAX_NANOSECONDS ((1L << 30) - 1)
39
40 #define CASE_NAME_FORMAT "%s: msb:%x lower_bound:%x extra_bits: %x"
41
42 #define LOWER_BOUND_NEG_NO_EXTRA_BITS_CASE\
43 "1901-12-13 Lower bound of 32bit < 0 timestamp, no extra bits"
44 #define UPPER_BOUND_NEG_NO_EXTRA_BITS_CASE\
45 "1969-12-31 Upper bound of 32bit < 0 timestamp, no extra bits"
46 #define LOWER_BOUND_NONNEG_NO_EXTRA_BITS_CASE\
47 "1970-01-01 Lower bound of 32bit >=0 timestamp, no extra bits"
48 #define UPPER_BOUND_NONNEG_NO_EXTRA_BITS_CASE\
49 "2038-01-19 Upper bound of 32bit >=0 timestamp, no extra bits"
50 #define LOWER_BOUND_NEG_LO_1_CASE\
51 "2038-01-19 Lower bound of 32bit <0 timestamp, lo extra sec bit on"
52 #define UPPER_BOUND_NEG_LO_1_CASE\
53 "2106-02-07 Upper bound of 32bit <0 timestamp, lo extra sec bit on"
54 #define LOWER_BOUND_NONNEG_LO_1_CASE\
55 "2106-02-07 Lower bound of 32bit >=0 timestamp, lo extra sec bit on"
56 #define UPPER_BOUND_NONNEG_LO_1_CASE\
57 "2174-02-25 Upper bound of 32bit >=0 timestamp, lo extra sec bit on"
58 #define LOWER_BOUND_NEG_HI_1_CASE\
59 "2174-02-25 Lower bound of 32bit <0 timestamp, hi extra sec bit on"
60 #define UPPER_BOUND_NEG_HI_1_CASE\
61 "2242-03-16 Upper bound of 32bit <0 timestamp, hi extra sec bit on"
62 #define LOWER_BOUND_NONNEG_HI_1_CASE\
63 "2242-03-16 Lower bound of 32bit >=0 timestamp, hi extra sec bit on"
64 #define UPPER_BOUND_NONNEG_HI_1_CASE\
65 "2310-04-04 Upper bound of 32bit >=0 timestamp, hi extra sec bit on"
66 #define UPPER_BOUND_NONNEG_HI_1_NS_1_CASE\
67 "2310-04-04 Upper bound of 32bit>=0 timestamp, hi extra sec bit 1. 1 ns"
68 #define LOWER_BOUND_NONNEG_HI_1_NS_MAX_CASE\
69 "2378-04-22 Lower bound of 32bit>= timestamp. Extra sec bits 1. Max ns"
70 #define LOWER_BOUND_NONNEG_EXTRA_BITS_1_CASE\
71 "2378-04-22 Lower bound of 32bit >=0 timestamp. All extra sec bits on"
72 #define UPPER_BOUND_NONNEG_EXTRA_BITS_1_CASE\
73 "2446-05-10 Upper bound of 32bit >=0 timestamp. All extra sec bits on"
74
75 struct timestamp_expectation {
76 const char *test_case_name;
77 struct timespec64 expected;
78 u32 extra_bits;
79 bool msb_set;
80 bool lower_bound;
81 };
82
get_32bit_time(const struct timestamp_expectation * const test)83 static time64_t get_32bit_time(const struct timestamp_expectation * const test)
84 {
85 if (test->msb_set) {
86 if (test->lower_bound)
87 return LOWER_MSB_1;
88
89 return UPPER_MSB_1;
90 }
91
92 if (test->lower_bound)
93 return LOWER_MSB_0;
94 return UPPER_MSB_0;
95 }
96
97
98 /*
99 * Test data is derived from the table in the Inode Timestamps section of
100 * Documentation/filesystems/ext4/inodes.rst.
101 */
inode_test_xtimestamp_decoding(struct kunit * test)102 static void inode_test_xtimestamp_decoding(struct kunit *test)
103 {
104 const struct timestamp_expectation test_data[] = {
105 {
106 .test_case_name = LOWER_BOUND_NEG_NO_EXTRA_BITS_CASE,
107 .msb_set = true,
108 .lower_bound = true,
109 .extra_bits = 0,
110 .expected = {.tv_sec = -0x80000000LL, .tv_nsec = 0L},
111 },
112
113 {
114 .test_case_name = UPPER_BOUND_NEG_NO_EXTRA_BITS_CASE,
115 .msb_set = true,
116 .lower_bound = false,
117 .extra_bits = 0,
118 .expected = {.tv_sec = -1LL, .tv_nsec = 0L},
119 },
120
121 {
122 .test_case_name = LOWER_BOUND_NONNEG_NO_EXTRA_BITS_CASE,
123 .msb_set = false,
124 .lower_bound = true,
125 .extra_bits = 0,
126 .expected = {0LL, 0L},
127 },
128
129 {
130 .test_case_name = UPPER_BOUND_NONNEG_NO_EXTRA_BITS_CASE,
131 .msb_set = false,
132 .lower_bound = false,
133 .extra_bits = 0,
134 .expected = {.tv_sec = 0x7fffffffLL, .tv_nsec = 0L},
135 },
136
137 {
138 .test_case_name = LOWER_BOUND_NEG_LO_1_CASE,
139 .msb_set = true,
140 .lower_bound = true,
141 .extra_bits = 1,
142 .expected = {.tv_sec = 0x80000000LL, .tv_nsec = 0L},
143 },
144
145 {
146 .test_case_name = UPPER_BOUND_NEG_LO_1_CASE,
147 .msb_set = true,
148 .lower_bound = false,
149 .extra_bits = 1,
150 .expected = {.tv_sec = 0xffffffffLL, .tv_nsec = 0L},
151 },
152
153 {
154 .test_case_name = LOWER_BOUND_NONNEG_LO_1_CASE,
155 .msb_set = false,
156 .lower_bound = true,
157 .extra_bits = 1,
158 .expected = {.tv_sec = 0x100000000LL, .tv_nsec = 0L},
159 },
160
161 {
162 .test_case_name = UPPER_BOUND_NONNEG_LO_1_CASE,
163 .msb_set = false,
164 .lower_bound = false,
165 .extra_bits = 1,
166 .expected = {.tv_sec = 0x17fffffffLL, .tv_nsec = 0L},
167 },
168
169 {
170 .test_case_name = LOWER_BOUND_NEG_HI_1_CASE,
171 .msb_set = true,
172 .lower_bound = true,
173 .extra_bits = 2,
174 .expected = {.tv_sec = 0x180000000LL, .tv_nsec = 0L},
175 },
176
177 {
178 .test_case_name = UPPER_BOUND_NEG_HI_1_CASE,
179 .msb_set = true,
180 .lower_bound = false,
181 .extra_bits = 2,
182 .expected = {.tv_sec = 0x1ffffffffLL, .tv_nsec = 0L},
183 },
184
185 {
186 .test_case_name = LOWER_BOUND_NONNEG_HI_1_CASE,
187 .msb_set = false,
188 .lower_bound = true,
189 .extra_bits = 2,
190 .expected = {.tv_sec = 0x200000000LL, .tv_nsec = 0L},
191 },
192
193 {
194 .test_case_name = UPPER_BOUND_NONNEG_HI_1_CASE,
195 .msb_set = false,
196 .lower_bound = false,
197 .extra_bits = 2,
198 .expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 0L},
199 },
200
201 {
202 .test_case_name = UPPER_BOUND_NONNEG_HI_1_NS_1_CASE,
203 .msb_set = false,
204 .lower_bound = false,
205 .extra_bits = 6,
206 .expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 1L},
207 },
208
209 {
210 .test_case_name = LOWER_BOUND_NONNEG_HI_1_NS_MAX_CASE,
211 .msb_set = false,
212 .lower_bound = true,
213 .extra_bits = 0xFFFFFFFF,
214 .expected = {.tv_sec = 0x300000000LL,
215 .tv_nsec = MAX_NANOSECONDS},
216 },
217
218 {
219 .test_case_name = LOWER_BOUND_NONNEG_EXTRA_BITS_1_CASE,
220 .msb_set = false,
221 .lower_bound = true,
222 .extra_bits = 3,
223 .expected = {.tv_sec = 0x300000000LL, .tv_nsec = 0L},
224 },
225
226 {
227 .test_case_name = UPPER_BOUND_NONNEG_EXTRA_BITS_1_CASE,
228 .msb_set = false,
229 .lower_bound = false,
230 .extra_bits = 3,
231 .expected = {.tv_sec = 0x37fffffffLL, .tv_nsec = 0L},
232 }
233 };
234
235 struct timespec64 timestamp;
236 int i;
237
238 for (i = 0; i < ARRAY_SIZE(test_data); ++i) {
239 timestamp.tv_sec = get_32bit_time(&test_data[i]);
240 ext4_decode_extra_time(×tamp,
241 cpu_to_le32(test_data[i].extra_bits));
242
243 KUNIT_EXPECT_EQ_MSG(test,
244 test_data[i].expected.tv_sec,
245 timestamp.tv_sec,
246 CASE_NAME_FORMAT,
247 test_data[i].test_case_name,
248 test_data[i].msb_set,
249 test_data[i].lower_bound,
250 test_data[i].extra_bits);
251 KUNIT_EXPECT_EQ_MSG(test,
252 test_data[i].expected.tv_nsec,
253 timestamp.tv_nsec,
254 CASE_NAME_FORMAT,
255 test_data[i].test_case_name,
256 test_data[i].msb_set,
257 test_data[i].lower_bound,
258 test_data[i].extra_bits);
259 }
260 }
261
262 static struct kunit_case ext4_inode_test_cases[] = {
263 KUNIT_CASE(inode_test_xtimestamp_decoding),
264 {}
265 };
266
267 static struct kunit_suite ext4_inode_test_suite = {
268 .name = "ext4_inode_test",
269 .test_cases = ext4_inode_test_cases,
270 };
271
272 kunit_test_suites(&ext4_inode_test_suite);
273
274 MODULE_LICENSE("GPL v2");
275